The invention relates to an apparatus for processing photographic materials (also referred to as a photo-processing machine) with a housing that accommodates at least one processing station.
In photo-processing machines, for example exposure devices that serve to project images onto photographic paper, in particular laser-based exposure devices, or in scanner devices that serve to scan developed photographic films, have a protective light-impermeable housing containing the individual processing stations by which the photographic material is processed. Devices of this kind work with a very high level of precision and at the same time with a very high processing speed. Because of the high precision and the fast processing speed, a processing station should be as much as possible kept free of any shocks or tremors while the system is in operation, as even the slightest disturbances can excite oscillations of the processing station with harmful effects on the desired quality of the work product.
To avoid shocks that can cause oscillations in the processing station, shock-damping measures are known as a state-of-the-art solution for damping any shocks that may occur.
As an example, DE 36 05 463 discloses a photo-processing system in which the processing station, while being enclosed in a housing, is fastened independently and directly to the floor through appropriate oscillation-damping elements. However, this concept presents the problem that shocks acting on the housing can be transmitted through the floor to the processing station in spite of the damping elements. The fine adjustment that is required when the equipment is installed presents a further problem, because the transfer of the light-sensitive material between the housing-mounted transport devices and the processing station requires a high degree of precision.
A scanning apparatus for photographic materials is disclosed in U.S. Pat. No. 4,417,260, where the scanning station is mounted in a housing by way of oscillation dampers. This concept likewise has the problem that possible shocks acting directly on the housing are transmitted to the processing station inside the housing.
The present invention therefore has the objective to propose a processing apparatus for photographic materials in which the quality of the work product is not negatively affected by the kind of shocks that occur in normal operating situations and may affect the housing or its immediate vicinity.
An apparatus for processing photographic materials in accordance with the invention has a housing and, enclosed in the housing, at least one processing station that performs a processing operation on the photographic materials. According to the invention, the housing and the processing station are connected exclusively through at least one common support base, and each of the housing and the processing station is attached through its own oscillation-damping connection to the common support base.
In the processing apparatus according to the invention, the connection between the housing and the processing station occurs exclusively along the indirect connection path through the common support base. Except for this indirect connection, the processing station is arranged inside the housing in total separation from the housing. Furthermore, the concept of connecting the processing station as well as the housing to the common support base through their own respective oscillation-damping mounts achieves two essential benefits. On the one hand, shocks affecting the housing are intercepted already by the damping connection between the housing and the support base, while on the other hand any oscillations that may nevertheless have reached the support base due to strong impacts on the housing are prevented by the damping connection between the support base and the processing station from being transmitted to the processing station.
The oscillation-damped arrangement of the processing station inside the housing avoids the problem of oscillation-transmitting bridges between the modules, so that disturbances which in a normal operating system act on the housing or the support base are not transmitted to the processing station and as a result, the processing station will be able to deliver the desired high quality of the work product.
In a preferred embodiment of the inventive apparatus, the processing station is held through oscillation-damping connections in an intermediate frame which, in turn is fastened to the support base. As a result of this arrangement, oscillations that may be transmitted to the intermediate frame are absorbed by the inertial mass of the frame.
In a particularly preferred arrangement, the intermediate frame is connected to the support base through oscillation-damping elements, whereby the overall damping effect is further enhanced.
Oscillations are also generated by the transport device by which the photographic materials are fed to the processing station. The invention therefore proposes an arrangement where the transport device for the photographic materials is not fastened directly to the processing station, but to a part of the intermediate frame in immediate proximity to the processing station. This concept prevents that oscillations originating from the transport device are transmitted to the processing station.
In order to prevent the risk that oscillations could be excited in the housing or the intermediate frame as a result of shocks or disturbances, it is further proposed to arrange dead weights at specific locations of the housing and/or the intermediate frame in order to increase the mass of the housing and/or the intermediate frame, so that the mass to be excited into oscillation in the event of a shock would have a high amount of inertia. This concept further improves the oscillation isolation of the processing station.
A further embodiment of the invention is particularly preferred if the apparatus is used to produce projected images on photographic materials such as a light-sensitive photographic paper either from a given graphic object or from digital image data. In this case, the invention proposes an arrangement where the attachment mounts of the processing station or, if provided, the attachment mounts of the intermediate frame, pass through light-sealed passage openings in the floor of the housing.
In order to allow a continuous working mode of photographic processing systems, it is customary to arrange docking stations at the housing for feeding and discharging devices, that serve to deliver additional photographic materials or remove processed materials while the system is in operation. To ensure that shocks caused by the docking of the feeding and discharging devices are transmitted to the apparatus housing only with a softened intensity, it is further proposed in accordance with the invention to provide at least one damping device per docking station to effectively dampen the docking and uncoupling movements of the feeding and discharging devices.
As a means for damping oscillations in all places mentioned in the foregoing description, it is preferred to use oscillation dampers that ensure the lowest possible resonance frequency of the system. The aim is for a resonance frequency below 30 Hz. An especially high degree of oscillation damping can be achieved if the resonance frequency of the system is below 15 Hz.
The principle of an oscillation isolation between the processing station and the housing in accordance with the foregoing description is used with particular preference in a photo-processing apparatus for exposing photographic materials. In this application of the invention, the processing station serves as exposure station in which images are projected onto photographic materials. Especially if the image on the photographic material is drawn by means of a laser light source, it is highly important that the processing station exposes the light-sensitive material without oscillations, because in a line-by-line exposure process of this kind even the slightest relative movements between the exposure station and the material being exposed are harmful to the quality of the end product. Oscillations transmitted into the exposure station manifest themselves in the output images through slight variations in the spacing between individual exposed image lines. The human eye is extremely sensitive especially to image defects of this nature and can recognize oscillations even if they are so slight that they can barely be registered with measuring instruments.
As a further area of application for the principle according to the invention, the inventive apparatus is used as a scanner device where the processing station serves to scan a developed film to produce the image data representing the original photographic image existing on the developed film. In this application, too, it is essential that the processing station not be subjected to oscillations during the scanning of the given graphic objects.